[TASK] Use correct property disqusLocale

TS was disqusLocale but code used disqusLang.
Switching to disqusLocale

Change-Id: I80cec6ab7c942e2d0991e804a797d72c74f497ec
Resolves: #54543
Reviewed-on: https://review.typo3.org/26562
Reviewed-by: Georg Ringer
Tested-by: Georg Ringer